[Amps] AL1200, RTTY contesting, temps, duty cycles (not 100%)

[Bill, W6WRT]

ORIGINAL MESSAGE:

On Wed, 01 Jul 2009 23:06:03 -0700, Kevin Normoyle <knormoyle at surfnetusa.com>
wrote:

>
>And how do you characterize the difference between RTTY 50% duty cycle for two hours, versus CW duty cycle for two hours?
>Does two hours matter? Why isn't a 30 minute test enough?

REPLY:

CW by its nature is an intermittent carrier whereas RTTY is 100%. Therefore, if
one is for example, ragchewing, where you talk half the time and the other guy
talks half the time, the net RTTY duty cycle would be 50%. By comparison, the CW
duty cycle would be only about 25%. This is why amps which are NOT
"bick-on-the-key" often have the same duty cycle ratings for CW and SSB, but
much less for RTTY.

Whether the rating is two hours or 30 minutes depends on the rate of heat
buildup in the box. A small box will build up heat faster than a large one, and
there are other factors too such as the physical size of the power transformer.

73, Bill W6WRT